Gear pump having internal bearings and seals



May 19, 1964 LUClANl 3,133,506

GEAR PUMP HAVING INTERNAL BEARINGS AND SEALS Filed Aug. 15, 1961 2 Sheets-Sheet 2 46 I V 44 mam? 4 Louis Lac/am L 011% yM g 56 United States Patent 3,133,506 GEAR PUMP HAVING INTERNAL BEARINGS AND SEALS Louis Luciani, 207 Roosevelt Ave., Torrington, Conn.

' Filed Aug. 15, 1961, Ser. No. 131,577

8 Claims. (Cl. 103-'126) This invention relates to new and useful improvements in gear pumps and has for its primary object to provide, in a manner as hereinafter set forth, a pump of this type in which both gears are provided with ball or other bearings and wherein, further, said bearings are enclosed in and thus protected by the respective gears.

Another very important object of the present invention is to provide an improved gear pump of the aforementioned character which embodies unique sealing means for further protecting the bearings against contamination by the material being pumped.

Another important object of the invention isto provide an improved pump of the character described wherein the bearings are sealed against contamination on both sides of both gears.

A further object of the present invention is to provide an improved gear pump comprising novel combined lubricating and visual leakage warning means for the internally mounted bearings. I 9 Another object of the invention is to provide a gear pump wherein the drive gear is integral with the drive shaft. e Other objects of the invention are to provide an'improved gear pump which will be comparatively simple in construction, highly eflicient and reliablein operation, exceedinglystrong, durable and rigid, compact and of relatively light weight, and which may be manufactured at low cost.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which;

FIGURE 1 is a view in vertical longitudinal section through an improved gear pump constructed in accordance with the'present invention;

FIGURE 2 is a view in transverse section, taken substantially on the line 22 of FIGURE 1;

FIGURE 3 is a cross-sectional view, taken substantially on the line 33 of FIGURE 1;

FIGURE 4 is a view in vertical longitudinal section through another embodiment of the pump; and

FIGURE 5 is a fragmentary view in vertical section through another modification.

Referring now to the drawing in detail, it will be seen that the embodiment of the present invention which has been illustrated in FIGURES l, 2 and 3 of said drawing comprises a metallic housing 6 of suitable dimensions. The housing 6 includes front and back plates 7 and 8, respectively. Mounted in the housing 6 on the inner faces of the plates 7 and 8 are wear plates 9. The back plate 8 of the housing 6 has formed integrally therewith and projecting therefrom a cylindrical hub or the like 10.

Mounted on the front plate 7 of the housing 6 and projecting into the chamber 11 of said housing are duplicate upper and lower stationary or idler shafts 12. Openings 13 in the plate 7 receive the outer end portions of the shafts 12. The shafts 12 include enlarged intermediate portions 14 providing shoulders 15 and 16. The shoulders 15v abut the plate 7. Nuts 17 are threaded on the projecting outer end portion of the shafts 12 for rigidly securing said shaft in position on the plate 7 in conjunction with the shoulders 15. Lock washers 18 are provided for the nuts 17.

Extending rotatably into the upper portion of the housing 6 through the back plate 8 and the hub 10 in spaced, concentric relationto the latter is a drive shaft 19 from a suitable source of power. The shaft 19 enters the housing 6 through a stainless steel bushing 20 in the plate 8. A packing gland 21, suitable for the material to be pumped, is provided for the shaft 19 in the plate 8. Adjusting screws 22 (FIG. 3) are provided for the packing 21. If desired, a mechanical seal may be substituted for the packing 21. The shaft 19 is journaled in a ball bearing 23 provided therefor in the outer end portion of the hub 10. A retaining cap 24 is provided for the hearing 23, said cap being secured on the free end of the hub 10.

Formed integrally with the inner or forward end of the shaft 19 for rotation about the upper stationary shaft 12 is a generally cup-shaped drive gear 26. A driven gear 27 of substantially similar construction is journaled on the lower shaft 12. As shown to advantage in FIGURE 2 of the drawing,'the gears 26 and 27 are meshed for, rotation in unison in the chamber 11 between the fluid inlet and outlet 28 and 29 of the housing 6. Ball bearings 30 are provided for the gears 26 and 27 on the inner end portions of the shafts 12. It will be noted that the front bearings 30 abut the shoulders 16 of the shafts 12. It also will be noted that each gear 26 and 27 is provided with a pair of bearings 30. Apertured spacing rings 31 are mounted on'the shafts 12 between the pairs of bearings 30 for providing chambers 32.

Extending centrally through the shafts 12 are 1ubricat-. ing ducts 33' for the bearings 30. Branches 34 in the inner' end portions of the shafts 12 communicate the' ducts 33 with the chambers 32. Oil cups or fittings 35 are provided on the outer ends of the shafts 12 in communication with the ducts 33. Cup washers 36 are se-' curedon the inner ends of the shafts 12'by bolts 37. Knockouts in the form of disks 38 are provided between the inner or rear sides of the gears 26 and 27; said knockouts having threaded openings 73 therein for receiving a suitable extracting medium or tool. The bolts 37 are provided with smooth 'bores 76 aligned with the threaded openings 73 and of a diameter to slidably accommodate the extracting instrument.

Packings comprising O-rings 39 are provided in the front wear plate 9 around the enlarged intermediate portions 14 of the shafts 12. Also mounted on the enlargements 14 of the shafts 12 are balanced mechanical seals 40 which positively seal the open ends or sides of the gears 26 and 27 in a manner to thoroughly protect the bearings 30 from the material passing through the pump. Threaded retaining rings 71 and O-rings 72 are provided in the open end or side portions of the gears 26 and 27. Suitable bolts 74 secure the housing assembly 6.

It is thought that the operation of the pump will be readily apparent from a consideration of the foregoing. Of course, the gear 26 drives the gear 27 and the material being pumped is impelled in the usual manner by said gears. Oil enters the reservoirs 32 from the cups 35 by gravity and keeps the bearings 30 thoroughly lubricated. The balanced mechanical packings or seals 40 prevent the material being pumped from entering the gears from the chamber 11 and the packings or seals 39 prevent leakage around the shafts 12. However, should the seals 40 fail and permit the material being pumped to enter the bearing chambers in the gears, said material will be forced through the lubricating system 32, 34 and 33 of each shaft 12 and emerge from the cups or fittings 35 thus providing a visual Warning that leakage is occurring. The construction and arrangement of parts would allow a positive clearance on both sides of the gears in relation to the wear plates or the housing plates if said wear plates are omitted. The rigidly mounted shafts 12 with their securing nuts 17 and lock washers 18 and comprising fixed shoulders next to the bearings allow at assembly a means fixing the distance from the bearings to the faces of the gears. This permits a positive amount of clearance. By controlling the length of the gears, this also allows a definite clearance between the gear faces and the back plate.

In FIGURE 4 of the drawing reference numeral 41 designates a housing comprising front and back plates 42 and 43, respectively. Mounted in openings 44 in the front plate 42 are stationary or idler shafts 45. Meshed drive and driven gears 46 and 47, respectively, are journaled on the upper and lower shafts 45, said drive gear 46 being integral with a drive shaft 48 from a suitable source of power. A suitable packing 49 is provided for the shaft 48. Suitable bolts (not shown) secure the housing assembly 41.

The shafts 45 include enlarged intermediate portions 50 providing shoulders 51 and 52, the former abutting the plate 42. Ball bearings 53 for the gears 46 and 47 are mounted on the inner end portions of the shafts 45 and abut the shoulders 52. Mounted in the gears 46 and 47 on the enlarged intermediate portions 50 of the shafts 45 are mechanical seals 54 which prevent the entrance of contaminated material from the chamber of the pump.

In the embodiment of FIGURE of the drawing, ref erence numeral 55 designates a housing comprising front and back plates 56 with Wear plates 57 on the inner faces thereof. Mounted in the lower portions of the plates 56 is a pair of aligned stationary or idler shafts 58 which are substantially similar to the shafts 12 in that said shafts 58 comprise enlarged intermediate portions 59 providing shoulders 60 and 61. Nuts 62 are threaded on the projecting outer end portions of the shafts 58 for rigidly securing said shafts in position in the plates 56 in conjunction With the shoulders 61, lock washers 63 being provided for said nuts. Lubricating ducts 64 are provided in the shafts 58 and extend from end to end thereof for lubricating spaced ball bearings 65 which are mounted on the inner end portions of said shafts in abutting engagement with the shoulders 60. Seals or packings 66, comprising O-rings, are mounted in the plates 57 and prevent leakage through said plates around the shafts 58. A tubular driven gear 67, open on both ends or sides, is rotatably supported on the shafts 58 by the bearings 65. Balanced mechanical seals 68 close the ends or sides of the driven gear 67 against the entry of contaminating material from the pump chamber. The outer ends of the shafts 58 are provided with oil cups or fittings 69. Suitable bolts (not shown) secure the housing assembly 55. Referring again to FIGURE 4 reference numeral 77 designates a conventional bypass valve on the plate 42.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as claimed.

What is claimed as new is as follows:

1. A gear pump comprising a housing defining a chamber, said housing including front and back plates, idler shafts having longitudinal bores formed therethrough mounted on the front plate and projecting therefrom into the chamber, a drive shaft journaled in the back plate, a cup-shaped drive gear integral with the drive shaft and rotatable on one of the idler shafts, a cup-shaped driven gear on another of the idler shafts and meshed with said drive gear, bearings in said gears and operable on the inner end portions of the idler shafts, seals in the gears between the chamber and the bearings, retaining nuts threaded on the outer end portions of the idler shafts, said idler shafts comprising enlarged intermediate portions encircled by the seals and providing spaced shoulders abutting the front plate and the bearings, extractor disks disposed in said gears inwardly of the corresponding bearings and including means aligned with the corresponding longitudinal bores and adapted to have an elongated extraction tool passed through said bore and removably engaged therewith for pulling said bearing and seals from within said gears.

2. A gear pump comprising a housing defining a chamber, said housing including front and back plates, idler shafts having longitudinal bores formed therethrough mounted on the front plate and projecting therefrom into the chamber, a drive shaft journaled in the back plate, a cup-shaped drive gear integral with the drive shaft and rotatable on one of the idler shafts, a cup-shaped driven gear on another of the idler shafts and meshed with said drive gear, hearings in said gears and operable on the inner end portions of the idler shafts, seals in the gears between the chamber and the bearings, retaining nuts threaded on the outer end portions of the idler shafts, said idler shafts comprising enlarged intermediate portions encircled by the seals and providing spaced shoulders abutting the front plate and the bearings, extractor disks disposed in said gears inwardly of the corresponding bearings and including means aligned with the corresponding longitudinal bores and adapted to have an elongated extraction tool passed through said bore and removably engaged therewith for pulling said bearing and seals from within said gears, said gears defining lubricant reservoirs for the bearings, said idler shafts having longitudinal oil ducts extending thereinto from the outer ends thereof and communicating with the reservoirs.

3. A gear pump comprising a housing defining a chamber, said housing including front and back plates and wear plates mounted thereon, spaced idler shafts having longitudinal bores formed therethrough mounted on and extending through the front plate and the respective wear plate and projecting into the chamber, a drive shaft journaled in the back plate and the respective wear plate, a generally cup-shaped drive gear integral with the drive shaft and rotatable on one of the idler shafts, a generally cup-shaped driven gear rotatable on the other idler shaft and meshed with the drive gear for actuation thereby, pairs of bearings for the gears mounted therein on the idler shafts, seals in the gears encircling the idler shafts between the chamber and the bearings, cup washers on the inner ends of the idler shafts, disks slidable in the gears between the closed ends thereof and said cup washers for extracting the bearings and the seals, said disks including means aligned with the corresponding longitudinal bores and adapted to have an elongated extraction tool passing through said bores and removably engaged therewith for pulling said bearings and seals from Within said gears, and retaining nuts for the idler shafts threaded on the outer end portions thereof.

4. A gear pump in accordance with claim 3, together with spacing rings on the idler shafts between the pairs of bearings.

5. A gear pump in accordance with claim 4, wherein said gears define lubricant reservoirs for the bearings, said longitudinal bores also defining ducts therein communicating with the reservoirs.

6. A gear pump comprising a housing defining a chambet and including a removable closure plate for said chamber, parallel shafts supported from said housing and having corresponding ends projecting into the chamber and including longitudinal bores, meshed cup-shaped gears in said chamber and rotatable on said ends, bearings in said gears operable on said shaft ends, disks slidable in said gears between the closed ends thereof and said bearings and including means aligned with the corresponding longitudinal bores and adapted to have an elongated extraction tool passed through said bores and removably engaged therewith for pulling saidbearings and seals from within said gears.

7. A gear pump in accordance with claim 6, said means 6 comprising threaded openings formed in said disks for connecting an extracting tool thereto.

8. A gear pump in accordance with claim 7, said shafts having lubricant ducts therein aligned with the openings for the insertion of the tool.

References Cited in the file of this patent UNITED STATES PATENTS 1,418,741 Stallman June 6, 1922 1,689,673 Lalor Oct. 30, 1928 2,847,157 Nilsson Aug. 12, 1958 3,031,130 Persson Apr. 24, 1962 FOREIGN PATENTS 328,963 Germany Nov. 11, 1920 1,152,879 France Sept. 16, 1957 

1. A GEAR PUMP COMPRISING A HOUSING DEFINING A CHAMBER, SAID HOUSING INCLUDING FRONT AND BACK PLATES, IDLER SHAFTS HAVING LONGITUDINAL BORES FORMED THERETHROUGH MOUNTED ON THE FRONT PLATE AND PROJECTING THEREFROM INTO THE CHAMBER, A DRIVE SHAFT JOURNALED IN THE BACK PLATE, A CUP-SHAPED DRIVE GEAR INTEGRAL WITH THE DRIVE SHAFT AND ROTATABLE ON ONE OF THE IDLER SHAFTS, A CUP-SHAPED DRIVEN GEAR ON ANOTHER OF THE IDLER SHAFTS AND MESHED WITH SAID DRIVE GEAR, BEARINGS IN SAID GEARS AND OPERABLE ON THE INNER END PORTIONS OF THE IDLER SHAFTS, SEALS IN THE GEARS BETWEEN THE CHAMBER AND THE BEARINGS, RETAINING NUTS THREADED ON THE OUTER END PORTIONS OF THE IDLER SHAFTS SAID IDLER SHAFTS COMPRISING ENLARGED INTERMEDIATE PORTIONS ENCIRCLED BY THE SEALS AND PROVIDING SPACED SHOULDERS ABUTTING THE FRONT PLATE AND THE BEARINGS, EXTRACTOR DISKS DISPOSED IN SAID GEARS INWARDLY OF THE CORRESPONDING BEARINGS AND INCLUDING MEANS ALIGNED WITH THE CORRESPONDING LONGITUDINAL BORES AND ADAPTED TO HAVE AN ELONGATED EXTRACTION TOOL PASSED THROUGH SAID BORE AND REMOVABLY ENGAGED THEREWITH FOR PULLING SAID BEARING AND SEALS FROM WITHIN SAID GEARS. 